In a conventional internal combustion engine, either a reciprocating-type engine or a rotary-type engine, a separate auxiliary device such as a starter motor and large battery are often provided in order to start the engine. In such an engine, the starter motor draws power from the battery in order to turn a flywheel, which, in turn, rotates the engine's crankshaft. In a four-stroke engine, a starter motor must provide sufficient power to rotate the crankshaft enough to complete a compression stroke. Once a compression stroke is completed, the engine fires the compressed charge and thus begins normal engine operation.
When an internal combustion engine is turned off by an operator (e.g., a key switch is disengaged or a choke valve is closed), the engine stops by stopping the combustion in its chambers by simply ceasing the delivery fuel and/or air to the combustion chambers. With no combustion in the chambers, the crankshaft stops rotating and the engine stops. In such an engine, however, there is no control over where the crankshaft (and thus also the pistons) come to rest.